A source toldUs Weekly that the Flip or Flop star and Ant are an item after romance rumors sparked on Monday thanks to the new couple's activity on social media.
Christina, 34, posted a picture with the U.K.'s former For the Love of Cars host, 38, on Instagram during a bike ride together on Monday. The pair were smiling and happy, and they were both sporting dark sunglasses.
"Congrats to this guy @ant_anstead His show, #WheelerDealers airs in the UK today! #HMF," Christina captioned the cute selfie.
Christina seemed to validate dating speculation when she subsequently commented to nutritionist Cara Clark on her Instagram account that they should go on a "double date soon" with their significant others.
The HGTV reality star's realtor friend, Deborah Linden, also wrote the following in Christina's comments section: "Great to see a post of you together," to which Christina responded, "lol, Thank you!! Happy New Year."
And one day earlier on December 31, the blonde beauty and mother of two posted a quote on Instagram that read, "And suddenly you know... It's time to start something new and trust the magic of beginnings."
The quote alluded to a possible new love interest, as she wrote alongside the image, "New beginnings."
The real estate investor and house flipper added, "2018 is going to be a great year filled with new experiences, challenges and blessings. Excited for the next chapter."
Christina and Ant both shared posts on social media from Newport Beach, CA, this past weekend, so it's likely they spent several days together.
As previously reported, Christina publicly announced her split from her estranged husband Tarek El Moussa in December 2016, although they separated in May of that year after a blowout fight.
Christina and Tarek share daughter Taylor, 7, and son Brayden, 2, and they continued to filmFlip or Flop together despite their failed marriage.
Prior to getting romantically involved with Ant, Christina dated businessman Doug Spedding, but they broke up in October 2017 once he entered rehab to treat his substance abuse issues. She had also been linked to her family's former contractor Gary Anderson.
As for Ant, the motor specialist and car builder split from his wife, Louise Anstead, in July 2017.